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Updated: Jun 24, 2026
08:06
Genome-wide Determination of Mammalian Replication Timing by DNA Content Measurement
Published on: January 19, 2017
Replication timing and transcriptional control: beyond cause and effect--part II
Ichiro Hiratani1, Shin-ichiro Takebayashi, Junjie Lu
1Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA.
Current Opinion in Genetics & Development
|April 7, 2009
Summary
Cellular differentiation involves coordinated shifts in DNA replication timing and transcription. These large-scale changes correlate with nuclear repositioning and altered promoter activity during S-phase.
Area of Science:
- Genomics
- Epigenetics
- Cell Biology
Background:
- Replication timing's link to transcription is often oversimplified.
- Mechanisms regulating DNA replication initiation remain poorly understood.
- Previous studies relied on limited gene analyses in cell lines.
Purpose of the Study:
- To investigate genome-wide replication timing changes during cellular differentiation.
- To explore the relationship between replication timing, transcription, and subnuclear organization.
- To identify key S-phase transitions and their associated regulatory events.
Main Methods:
- Genome-wide analyses of replication timing.
- Assessment of transcriptional activity.
- Tracking of subnuclear repositioning.
- Analysis of chromatin structure.
Main Results:
- Cellular differentiation shows coordinated changes in replication timing and transcription.
- Replication timing shifts occur in megabase-sized domains, not just localized regions.
- These changes are linked to subnuclear repositioning.
- A critical S-phase transition is proposed, associated with promoter activity changes.
Conclusions:
- Replication timing, transcription, and subnuclear organization are coordinated during differentiation.
- Large-scale genomic domains, not just local chromatin, dictate replication timing.
- A mid-S-phase transition point influences promoter activity and nuclear positioning.
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